1. Field of the Invention
The present invention relates to an optical information recording medium, and more particularly to a phase-change optical information recording medium in which information is recorded, reproduced and rewritten by changing an optical property of a material in the phase-change recording layer thereof by irradiating the recording layer with a light beam.
2. Discussion of the Related Art
Japanese Patent No. 02652443 (i.e., Japanese Laid-Open Patent Publication No. 1-220126, hereinafter JP'443) discloses a method for recording information, such as address information for EFM signals with respect to CD-RW, in an information carrier 11 as shown in FIG. 6A. In addition, JP'443 discloses a method in which a wobbling groove is used to input address information with respect to DVD. FIGS. 6C and 6D are enlarged views of a portion 12 of the information carrier 11 shown in FIG. 6A, and FIG. 6B is a cross-section of the information carrier 11 when the carrier is cut at a line b—b shown in FIG. 6A. As shown in FIG. 6B, the information carrier 11 has a sinusoidally wobbling servo track 14. In FIG. 6B, numerals 15, 16 and 17 denote a transparent substrate, a recording layer and a protective layer, respectively. It is described in JP'443 that the servo track 14 has a frequency component which is produced by track modulation and which has an average frequency of 22.05 KHz, and that the frequency of the track modulation is modulated according to position information signals. However, in formation to be input in the information carrier has to satisfy the respective specified conditions for each application, and therefore when a disk is manufactured, the groove and recording layer have to be optimized so as to be suited for the application. The recording medium of the present invention satisfies the disk standards of 4.7 GB DVD+RW. An optical information recording medium satisfying the standards has not yet been disclosed.
Recently, rewritable optical disks which have the same capacity as high density DVD-ROMs and in which information can be recorded at the same speed as that for high density DVD-ROMs. These rewritable optical disks typically have a wobbling guide groove in their substrate to read and write information therein, and information such as clock information and address information of signals is input in the guide groove.
Because of these reasons, a need exists for a rewritable optical information recording medium which has the same capacity as high density DVD-ROMs and good recording properties even when information is recorded at a high speed.